They do a tour of the theater, which is well worth the money. The stage does so many things and the Navy used it as a template for aircraft-carrier construction during WW II. In fact, there were soldiers stationed in the bowels of the theater during the war to protect against espionage.

As for the steam heat, when ConEd is involved, all you see is the line coming in from the steet, followed by a steam meter and two PRVs in series. I can show it to you at The General Society if you get to Manhattan. That building is worth the trip.

I've seen numerous industrial facilities forgoing condensate recovery. And I've seen brave attempts to pump back the condensate. As an engineer I championed the latter. But now with hindsight I've changed my mind. Those boiler operators who dumped condensate were experienced.

Which brings me back to history of steam heating. Companies like DunhamBush have to sell stuff. But the best steam heating didn't use traps,vents,or pumps? Something like the ancient Moline design?

Many ConEd-supplied steam systems have vacuum pumps. The Empire State Building is a good example. The vacuum pump allows the design engineer to downsize all the pipes, valves, and fittings because of the pressure-to-vacuum differential. The difference between ConEd steam and a boiler-provided steam is that ConEd doesn't want the customer to return the condensate. That would be very difficult since some of the customers would have to pump the condensate several miles under the NYC streets. There's no piping network for this and the transfer pumps would be enormous. I can't even imagine the size of the boiler-feed receiver ConEd would have to have to accommodate all that returned condensate.

Yes. I've seen one in some NYC building. ConEd steam goes into a large tank & condensate drains out. Heating steam comes out from the tank & condensate from building heating system comes back to be reboiled by more ConEd steam. Controller for the ConEd steam looks similar to PRV. So that tank is a heat exchanger but I cannot see what the benefit is? Unless ConEd steam contains CO2 ? I doubt that.

In factories the advantage is that primary condensate is under higher pressure so easier to feed back into boiler. But when dumping steam????